Cooled turbine or compressor blade



June 9, 1953 s. B. WILLIAMS 2,641,439

June 9, 1953 s. B. WILLIAMS cooLED TURBINE 0R COMPRESSOR BLADE 3Sheets-Sheet 2 Filed 0G12. 1, 1947 June 9, 1953 s. B. WILLIAMS cooLEnTURBINE 0R COMPRESSOR BLADE:

5 Sheets-Sheet 5 Filed 001,. 1, 194'? INVENTOR. Samye] MZL'ama BYFF/YEKS Patented June 9, 1953 UNITED PATENT QFFICE 'OL) *B OR CVPRSSOR LB. Williams, Deiroit, Mieli., assigner to Chrysler Corporation, HighlandPark, Mich.; a corporation 'of Delaware Application (')toli 1, 1947-;Serial No; 7?753150 i2 Claims.

l This applicationrel'ate's to a structure passages therein. Morespecically, it relates t the production of an cbject, which maybe 'atl`1`r= bine blade or ine like :having cooling passages 'formed therein.

Arifobject of the present invention is to 'pro' vide fr the production fan article having a pllll'ialit'y` o f `passages' therein, which may be'small 'iii S`iz'e l ar`1d relatively 4close to the Surface fr the' sakeof cooling thearticle.

Cth'er 'objects Will appear from the disclosure. In the drawings: Iynig. 1 is a plan view or a blank of 'which a tuibino blade is to berefined:

Fig. 2 is a setl View taken alofl'g the li'r 1 `zv2 of Fig'. 1;

Figs. 3, 4, and 5 are sectional views similar to Fig. "2 showing inoblank after' successive steps have been formed upon it; nig. 6 'is asectional View taken along 'the line 6-6 of Fig., 1;

Figs. "ia-nd 8 are seotionalvviews talgenalong the lines '1 1 and en -'safter the steps'illustiatod in 'Figa 3, 4, and 5 have been performed'upon Athe blank; f tige a view of a completed blade -foirled yfrom theblank; and

liigs. 1 and are -sectiolrialnviewstakeh along the y'lines -Iil--Ill andH1-II of Fig. 9

Fig. 1 snows a lblank lg from which ya turbina 'blade is to be 'fomjedfrne blank lo has -agnxgt Aportion II through which an opening I2 islformed. 4'leyond the outer end of the open-ing I2 in the blade portionproper o f the Ablank I U, there is 4formed in the surface of the blankaplurality of ridges I3 between which are formed grooves I4. Most of thegrooves and ridges curve near their outer en ds and terminate in thefinanci-one edge of the blank I0'. lCertain ridges t3 terminating in thetip vof theblank .grow noticeably wider Iat the tip of the blankandthereby im crease the spacing of the grooves lvI4 formed 'betweenthem. The 4blank I' is approximately uniform in width throughout the:greater part `of the lblade portion vproper and commen-ces tod-imnishin Width at a region near the :root II. Just before the blank commencesto 'diminish in Widthy alternate ridges I3 terminate; nearer the root `II, alternate ones 'of the remaining ridges terminate; and vfinally threeridges runas =far as the vouter "end 'of the opening I2, where 'theyterminate and their upper surfaces merge with the 'surface of the blank`as indicated at I5 in Figs. l and b1li-. As indicated -in Fig. 1l, thegrooves vI4 are yrelatively shallow throughout the having 2 part Aof theblade portion proper that is of lurl-ivform width and then increase indepth `at 'the region Where the yblank commences to .narrow and mergesmoothly at their bottoms IWith the bottom of the opening I2.

The `blank I0 With its passage I2, ridges I3., and grooves I4 may beformed of Stellite lby precision casting. Thereupon the grooves "I4 arelled with a suitable -lling material such as aluminum, cadmium, Yor agraphiteeccntaining wax. The filling material is indicated 'by thereference character I6. Thereupon one side iof the blank I0,- which maypredominantly be 'cobalt is plated with a suitable `metal suchlas nickelby a process such as '-electrodeposition. The plating, which isindicated 'by reference charac ter Il, .extends over the surface -15adjacent `the root I I 'and over the ridges I3 andthe 'llingma terial Iin the grooves I4. Then a coating or plating I8, which may be chromium,lis 'applied to the nickel coating Il, for example, by the process ofelectrodepositon. Next the Illing -'material I6 is 'removed through thepassages 19 fiormed bythe grooves I3 and 'thepl'atings I'l and I8. vWhenthe filling material is aluminum, it may -b'e removed by' caustic soda.When vthe' 'lli "ing material is cadmium, it may be removed` y heatingto vaporization. When the filling nii'ae y'i'.er-al -i 'agraphite-containing Wax, Ait inyibe 'frelnflca'ved by melting. Finally'the bond between the plating and blank l0 may be strengthened 7lbyappropriate Lheat treating to make *the nickel plating lalloy with thechromium plating and with the cobalt blank I0.

As seen in Figs. 9, `1(),^and '1l'1,'the turbine blade fo'r'med by theyprocess just described, hasl ashelftlike portion '|99a projecting fromthe concav'eis'ide 4of the blade. This vportion serves to space theblade from an adjacent blade, which is not 'lsho'vv'h. Reinforcing ribs'or flanges i20, 32|, fanti '22 de'pend `-ifrf` rr1-fthe shelf-"likeportions 19a.

yIn 'operation the vb l'adewill be -rotated while be ing attached"through the root 'portion 'I I, 'which is radially innermost. Air :willflow through :cenltrifugal action V orb'y reasonof 'anfavailabl'e presvVsore dinerentialr'adially outwardly, or yupwardly 'as seenin Figfl,ythrough the blade. lThe 'a''r enter-s the opening -I 2 'and :continueson through the passages I9 "ii'n'ally escaping l'rom the blade at oneledge and at the tip. vThe`1`9ll`l20-Sefof fthe air passing through thebladeiisto'eoolthe ibl'ade. The cooling .is yeffective Abecause 'thepa'ssa'gesiar'e shallow throughout most o'fthe 1en`gthen'ed=bladeallowing zhigh ow velocities `v'vith acomp'ar'ati'vely smallfamount-ofcoolant now-ing,

The above described process for forming the passages I9 and blade makeit possible for the passages to be relatively shallow.

I claim:

1. A blade comprising a cast metal member having a plurality of ridgesand grooves between the ridges and electrolytically deposited platingmetal covering and alloyed with the ridges. and bridging the grooves soas to cooperate with the grooves to form cooling passages adjacent onesurface of the blade, said blade having a hub portion provided with anopening with Vwhich said grooves and passages establish communication,said grooves corresponding in num'berto said passages and including atleast first;'seco'nd`,' and third sets of grooves in series by sets inthat order leading toward the hub opening, saidsecond set of groovesbeing fewer in number than said rst set and said third setbeing--fewer'in number than said second set, said first set of groovescombining at least by twos to'formzthe grooves of said second set andsaid second set of grooves combining at least ,by twos to form thegrooves of said third set.

2. A blade comprising a cast metal member having a hub portion providedwith an opening and a blade portion having a plurality of ridges on oneside and grooves between them communieating with thehub opening, some ofvthe ridges vextending to the hub portion, and plating metal coveringthe ridges` and bridging the grooves so as to cooperate with the groovesto form cooling passagescommunicating with the hub opening.`

3. A blade comprising a cast metal member having av hub portion providedwith an opening and a'bladeportion having a plurality -ofcurved ridgeson' one side deflningegrooves and terminating in the blade ,tip andaside edge and communicating with the'hub opening, some of the ridgesextending tothe hub portion, other ridges terminating in spaced relationto the hub portion, still Vother ridges terminating in more ,greatlyspaced relation to the hub portion, the grooves decreasing in vdepthfrom the hub portion .tothe tip, and plating metal covering the ridgesand bridging the grooves so as to' combine withxthe grooves to formv`cooling passages" adjacent one side ofthe blade.l j 4 g' e fl.4 Theblade specified inclairn 3,1m@ cast metal member being of Stellite, andthe plating metal .being niekel-y f .5.' `The Yblade Speeedinelaimg@.the pas? metal .member beine .0f Stellite., andthe plei'neymetal beingnickel, the blade further includinga a coatme ef chromium 01,1 the,niekeL j. A lstructure comprisingA a metallicpartj, having an opening inone end and an external surface provided withrridges andrgroovesbetweenthe Mr ilvihges',andy a metallic electro-plating covering the ridges andbridging the grooves to cooperate with the grooves to4 formvpassagescorresponding in number to thevnumber of grooves, vsaidplurality of/grooves establishing communication .with said opening andincluding at least first,` second and third sets of grooves in series bysets in that order leading vtoward. said opening, said second set ofgrooves being of .afewer number thanthe first set, and said third set ofgrooves l.being ofa fewer number than the secondset, said-firstfset ofgrooves-combining at least by twos to formthe 'grooves of said secondset and said second set of grooves combining atleast by twos traversedinternally by? awplurality of 'streams 'of the same fluid, said turbineblade having a hollow, open-ended root and a blade part proper connectedto the root and having a tip edge and two side edges, and aseries-connected progression of rst, second, and third groups ofinternal passages in said blade extending in that order fromperforations formed in at least one said edge yof the blade part properto the'hollow interior of the root, said rst group of passages combiningat least by twos to form said second group of passages and said secondgroup of passages combining atleast by twos to form said third group ofpassages.

v8. A blade according to claim 7, in which the tip edge and oneside edgecontain all the perfor- .ations aforesaid and in which the aggregatenumber of perforations corresponds to the number of passages in said rstgroup.

Ina,4 turbine blade proper having concave and convex faces andconsisting longways of a rootportion, a neck .portion and .a bladeportion having va tip edge, a relatively sharp side ,edge and arelatively round side edge; amotivefluid conductingsurfacemeans, saidmotive fluidconducting surface means being in ,thefoimpfa shelfaxedalong the neck-blade boundary.v and projecting normalwise from theconcave face, said motive fiuid conducting ,surface meansgb'ein'gadaptedto provide on-eside of agas-flow channel, and a coolant gasconductingsurface means, said coolant gas conducting surface means.internally traversing saidblade proper longways and 'denning coolingpassages establishing communication between said portions, said passagesemergingat an` angleto said blade proper longways, fromthe blade portionin openings along said sharpedge and said tip edge.

, 10. A rooted turbine blade vgradually vwidening from the root thereof.and having r angopen mouth atthe meterla ablede Section. Proper providedwith a tip edge and side edges, a throat connecting the blade sectionproper to `the root, and means f orrnrlg @progression offirst, second,and third Igroups ofcooling poresleading in vthat order from a tip andside edge toward the open' mouth of the bladeL/said secondv group ofpores being fewer in number thansaidirstfgroup and seid third. group..ef. leeres beine fewer hinunter than said second group, said firstgroupoffpores combining atv leastrby twos to,V form saids 'cond group, lsaidsecond group ofpores combiningA at least by twos to forrn'said thirdgroup.

" 11. A rooted turbine' blade f `radi'lally widening 'If-I 'omv theirootthereof and having an open mouth atl the' root enoLa bladesection properprovided with a tipedge and side v ed'ges`,a throat connecting the bladesection proper towthe root, and

means forming alprogre'ssio'n of first, second, and third groups ofcooling pores leading vin that order from at least the tipedge towardthe openmouth ofthe blaue,` said second group` @spores `being fewerin'number than said rst group and said third g'rouprof pores being fewerin numberthan said second group, .said first group of pores com'- biningat least by twosto'"formsaidsecondgroup, salid's'econd group of porescombining atleast by twosto form said third group. .f

12. 'A' rooted turbine blade having an open mouth'at 'the root end', ablade section properpro'- vided with a tip edge and side edges, a'throat connecting the blade section proper to` theroot, and'meansforming a'progres'sion of at 'least'first second, Yand third setsof cooling pores leading in that orderfrom-s'paced orifices inthe'tipfedge toward thev open mouth ofthe bla`de'said first-set ofpores'being 'equalin'number to saidoriicesfand combining at least bytwos to form said second set of pores and said second sei'I combining atleast by twos to form said third set.

SAMUEL B. WILLIAMS.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date Siegel Feb. 4, 1919 Rosenqvisi*I Aug. 6, 1929 Reuss Mar. 17,1936 Meyer Nov. 5, 1940 Zellbeck Sept. 29, 1942 Nachtman June 25, 1946FOREIGN PATENTS Number Country Date 319,622 Great Britain Dec. 18, 1930594,931 Germany Mar. 23, 1934 5 878,999 France Nov` 2, 1942 OTHERREFERENCES Haekhs Chemical Dictionary, 2nd Edition, Blakistons Son andCo., Philadelphia, 1937, `page 10 885.

Platingy January 1948, page 46.

